Comment by gorgoiler
15 hours ago
Possibly, but I suspect mobile turbines (aircraft) are unquietened (noisy) by design because they don’t really need to be quiet at 35000ft.
Presumably a static turbine is minimizing noisy thrust in exchange for torque while also exhausting through an expansion chamber surrounded by deflective earthworks or some other shielding. (Although the one in the article is indeed all outside in the open.)
No, they’ve been intentionally designing them to be quieter for decades because they are in hearing distance for quite a lot of miles during takeoff and landing. I suspect you can better insulate one on land though since you’re less constrained on size and weight.
actually they've down much quieter in the past 40 years. e.g. the 787 dreamliner has wavy bits on the exit of the nozzle that reduce efficiency by 1% in exchange for quieter operation because making the engine quieter reduces the amount and weight of noise insulation in the cabin
Oh of course, I didn’t mean to say that they weren’t as quiet as they need to be, only that there ought to be some obvious noise reduction opportunities once the requirement to be airborne is gone, and once the machine is being used for torque instead of thrust.